[Cake] FreeNet backhaul

[Jonathan Morton]

> On 7 Sep, 2018, at 1:37 am, Pete Heist <pete at heistp.net> wrote:
> 
> This router is an old ALIX with kernel 2.6.26, but on the other hand it does have hfsc + esfq (a variant of sfq with host fairness) deployed, so if it’s actually controlling the queue, one might suspect that sfq it could control inter-flow latency at least somewhat.

ESFQ has two important faults: it doesn't explicitly control the length of individual queues (only tail-drops when a global limit is reached), and it suffers from hash collisions at the full "birthday problem" rate.  So some of your measurement traffic is likely colliding with real traffic and suffering accordingly.

That still makes ESFQ far better than a dumb FIFO.

 - Jonathan Morton